JP2928541B2 - Flow control valve, pump and filter in liquid supply device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow control valve, a pump, and a filter in a liquid supply device, and more particularly, to a liquid provided with a liquid supply device and containing bubbles, a foamable liquid. The present invention relates to a flow path control valve, a pump, and a filter for separating gas and liquid in the apparatus.

For example, in the semiconductor device manufacturing process, there is a cleaning process for removing organic substances adhering to the wafer surface as an initial pretreatment and a diffusion / CVD pretreatment for the wafer. In this cleaning process, a mixture of a hydrogen peroxide solution and sulfuric acid is used. Liquids and liquids such as phosphoric acid are used as cleaning liquids. If air bubbles are generated or mixed in these liquids, the air bubbles adhere to the wafer surface, causing unevenness in the removal of organic substances by the cleaning liquid. Therefore, it is required to separate and remove gas from the liquid.

[Related Art] For example, in a semiconductor device manufacturing process, a mixed solution of a hydrogen peroxide solution and sulfuric acid or a cleaning solution composed of a liquid such as phosphoric acid is used to remove organic substances attached to the surface of a wafer. These cleaning liquids are stored in a cleaning processing tank, and when the cleaning processing is repeatedly performed, the liquid is contaminated, and the contamination adversely affects the wafer.

Therefore, conventionally, while the cleaning liquid is circulated by a pump, dust, particles and the like in the cleaning liquid are removed by a filter, and the cleaning liquid is always kept in a clean state.

[Problems to be Solved by the Invention] However, the hydrogen peroxide solution used as the cleaning liquid is a foaming liquid, and is used in a cleaning liquid at a place where a chemical reaction during wafer cleaning or a pressure change of a pump, a filter, or the like occurs. Air bubbles are generated in the cleaning solution, and air bubbles are mixed in when the cleaning liquid is supplied to the cleaning processing tank. Bubbles mixed during the cleaning adhere to the wafer surface, and unevenness occurs in removing organic substances by the cleaning liquid, thereby lowering the yield. Therefore, the cleaning liquid is kept stationary until bubbles are removed. However, since liquids such as sulfuric acid and phosphoric acid have high viscosity, the mixed bubbles cannot be easily removed and the efficiency of the cleaning treatment is reduced, and the yield is reduced. There is a problem that it decreases.

The present invention has been made to solve the above problems, and an object of the present invention is to reliably remove bubbles mixed in a liquid in a liquid supply device and to reliably separate a gas and a liquid. To provide a flow path control valve, a pump and a filter.

[Means for Solving the Problems] In order to achieve the above object, the invention of claim 1 of the present invention relating to a flow path control valve shuts off a liquid suction passage and a discharge passage between the liquid suction passage and the discharge passage. And a diaphragm provided on the outer peripheral surface of the valve body. The flow control valve in the liquid supply device, wherein the diaphragm has a large number of through-holes formed therein, and repellent on both surfaces thereof. An aqueous film is adhered, and bubbles in the liquid are exhausted from the exhaust passage through the diaphragm.

The invention according to claim 2 of the present invention relates to a pump, wherein a liquid suction passage and a discharge passage, a liquid chamber provided between the suction passage and the discharge passage, and a liquid chamber provided in the liquid chamber are provided. A pump in a liquid supply device having a diaphragm for contraction or expansion, wherein the diaphragm has a large number of through holes formed thereon, and a water-repellent film is applied to both surfaces thereof, and Are exhausted to the exhaust passage via the diaphragm.

Further, the invention according to claim 3 of the present application relates to a filter, wherein the first suction port for sucking the liquid, the first discharge port for discharging the liquid, and the first suction port and the discharge port are provided between the first suction port and the discharge port. And
A support member having a main passage connected to the first discharge port;
A first disk connected to the support member;
A second suction port, which is connected to the first discharge port and sucks the liquid, a second discharge port from which the liquid is discharged, and a filter section of the second suction port and the discharge port. A first filter provided with a support member provided between the support member and having a main passage connected to the exhaust passage; and a second filter portion having a second disk connected to the support member. Has a plurality of through-holes formed therein and a branch passage connected to the main passage therein, and a hydrophilic film is adhered to the surface thereof, and the second disk has a large number of through-holes. A water-repellent film is provided on a surface of a branch passage formed and connected to the main passage, and the surface of the branch passage is coated with a water-repellent film. The filter section is configured to exhaust bubbles in the liquid to an exhaust passage.

[Operation] Therefore, according to the first and second aspects of the present invention, between the suction passage and the discharge passage, air bubbles having a small surface tension are removed from the water-repellent surface of the diaphragm provided in the flow path control valve or the pump. The liquid that has been removed through the holes and from which bubbles have been removed is exhausted to an exhaust passage.

In the invention of claim 3 of the present application, in the first filter portion between the first suction port and the first discharge port, the gas containing the gas and the liquid are mixed with the hydrophilicity of the first disk. After passing through the surface and through-holes, the liquid is filtered into dust and the like. Thereafter, in the second filter portion between the second suction port and the second discharge port, the liquid is converted into bubbles having a small surface tension.
Removed through the water-repellent surface and through-holes of the disc,
The liquid from which the bubbles have been removed is exhausted to an exhaust passage.

[Embodiment] An embodiment in which the present invention is embodied in a wafer cleaning liquid high supply apparatus in the manufacture of semiconductor devices will be described below with reference to the drawings.

FIG. 1 is a schematic configuration diagram showing a cleaning liquid supply device according to one embodiment of the present invention, FIG. 2 is a partial cross-sectional view in the axial direction of the pipe, FIG. 3 is a cross-sectional view in the diameter direction of the pipe, and FIG. FIG. 5 is an enlarged sectional view showing a principal part of a diaphragm, FIG. 6 is a sectional view showing a pump, FIG. 7 is an enlarged sectional view showing a principal part of a diaphragm, FIG. FIG. 9 is a cross-sectional view showing the filter, and FIG. 9 is an enlarged cross-sectional view showing a main part of the disk.

As shown in FIG. 1, a liquid mixture of a hydrogen peroxide solution and sulfuric acid or a liquid such as phosphoric acid is stored in each cleaning treatment tank 11 as a cleaning liquid, and a wafer is immersed in these cleaning liquids to remove organic substances on the surface. Is performed.

The cleaning liquid in each cleaning tank 11 is circulated through a liquid supply means including a pipe 12, a plurality of flow control valves 13, a circulation pump 14, a filter 15, and the like. Each flow path control valve 13 and pump
In 14, compressed air is supplied from a compressor (not shown) via an air pipe 16. An electromagnetic valve 17 is provided in each of the air pipes 16 upstream of each of the flow path control valves 13, and supply and cutoff of compressed air to each of the flow path control valves 13 is performed by opening and closing each of the electromagnetic valves 17.

As shown in FIGS. 2 and 3, the pipe 12 is an outer pipe 1 made of fluororesin.
It has a double structure of 8 and a fluororesin inner tube 19 provided with spacers 19a on the peripheral surface. A large number of through holes 20 are formed in the inner tube 19, and a water repellent film 21 is thermally separated on the inner peripheral surface thereof. The water-repellent film 21 has such a property that a substance having a small surface tension is allowed to pass, but a substance having a large surface tension is not allowed to pass. Accordingly, the cleaning liquid in the cleaning treatment tank 11 is
During the passage through the inside 19, only bubbles having a small surface tension pass through the water-repellent film 21 and are exhausted through the through hole 20 and the gap between the outer tube 18 and the inner tube 19, and the liquid having a large surface tension is Water repellent film 21
Flows through the inner pipe 19 without passing through the inner pipe 19.

FIGS. 4 and 5 show the flow path control valve 13, in which a piston 23 is slidably housed in a cylinder 22, and first and second pressure chambers 22a and 22b are formed above and below the piston 23. I have. First
The second pressure chambers 22a and 22b are connected to the solenoid valve 17 via air ports 24 and 25, and when the first pressure chamber 22a is supplied with compressed air, the second pressure chamber 22b communicates with the atmosphere. When the compressed air is supplied to the second pressure chamber 22b, the first pressure chamber 22a communicates with the atmosphere.

A valve body 27 made of soft resin is screwed to a lower end of the piston 23 via a spacer 26. The valve body 27 always shuts off the cleaning liquid suction passage 29 and the discharge passage 30 by the urging force of the spring 28 provided on the upper surface of the piston 23 and the pressure of the compressed air supplied into the first pressure chamber 22a. It is urged in the direction to be. When compressed air is supplied to the second pressure chamber 22b and the first pressure chamber 22a is communicated with the atmosphere,
The valve body 27 moves upward together with the piston 23, connects the suction passage 29 and the discharge passage 30, and allows the cleaning liquid to pass therethrough.

As shown in FIG. 5, a diaphragm 31 is integrally formed on the outer peripheral surface of the valve body 27, and a large number of through holes 31a are formed in the diaphragm 31, and a water-repellent film 32 is formed on both surfaces thereof.
Are heat-sealed. Then, the suction and discharge passages 29, 30
While the suction and discharge passages 29 and 30 are in communication with each other, only bubbles in the cleaning liquid are removed by the water-repellent film 32.
And the exhaust passage 33 provided in the cylinder 22 through the through hole 31a.
It is guided and exhausted.

6 and 7 show the pump 14. A plunger 35 is slidably provided in a cylinder block 34 arranged at the center of the pump 14. The plunger 35 is moved in the left-right direction by a compressed air control device 36 formed in the cylinder block 34. Is reciprocated. Diaphragms 37 are attached to both ends of the plunger 35, respectively. A first liquid chamber 38 and a first air chamber 39 are formed on the left side of the cylinder block 34 by the respective dial flams 37, and a second liquid chamber 38 is formed on the right side of the cylinder block 34. A liquid chamber 40 and a second air chamber 41 are formed. The first and second liquid chambers 38, 40 are connected to the suction passage 44 and the discharge passage 4 for the cleaning liquid via check valves 42, 43.
Connected to 5.

Accordingly, when the plunger 35 is moved to the left in FIG. 6, the first liquid chamber 38 is reduced and the second liquid chamber 40 is expanded. At this time, the check valve 42 opens in the second liquid chamber 40,
The check valve 43 is closed and the cleaning liquid is sucked into the second liquid chamber 40 from the suction passage 44. In the first liquid chamber 38, the check valve 42 closes and the check valve 43 opens, so that the cleaning liquid in the first liquid chamber 38 is discharged through the discharge passage 45. When the plunger 35 is moved rightward in FIG. 6, the first liquid chamber 38 is enlarged and the second liquid chamber 40 is expanded.
Is reduced, the cleaning liquid is sucked into the first liquid chamber 38, and the cleaning liquid is discharged from the second liquid chamber 40.

As shown in FIG. 7, each diaphragm 37 has many through holes.
37a is formed, and a water-repellent film 46 as a bubble removing means is thermally separated on the surface thereof. When the pressure in each of the liquid chambers 38 and 40 is increased by reducing the size of the first or second liquid chambers 38 and 40, only bubbles in the cleaning liquid are removed by the water repellent film 46.
And is exhausted from the through hole 37a via an exhaust passage (not shown).

FIGS. 8 and 9 show a filter 15 provided downstream of the pump 14, a first filter 15A for removing dirt, particles and the like in the cleaning liquid, and a filter 15A for removing air bubbles mixed in the cleaning liquid. And a second filter 15B.

The first filter 15A is provided with connections 48, 49 on the left and right sides of a cylindrical body 47. The cleaning liquid is sucked from the connection port 49 and discharged from the connection port 48. Further, a stopper 51 is screwed into the sealing port 50, and when gas accumulates in the body 47, the accumulated gas can be discharged by opening the sealing port 50.

A mounting member 52 projecting from the inside of the body 47 corresponding to the connection port 48 has a support member having a passage 54 extending in the axial direction.
A plurality of disks 55 pass through the support member 53 at a predetermined interval and are supported and fixed to the support member 53. Ninth
As shown in the figure, a large number of through holes 55a are formed in each disk 55, and a passage 56 communicating with the passage 54 of the support member 53 and communicating with the plurality of through holes 55a (one in this embodiment). Only shown). Further, a hydrophilic film 57 that allows only gas and liquid to pass therethrough is heat-sealed to the surface of each disk 55. Then, dust, particles, and the like in the cleaning liquid sucked from the connection port 49 are filtered by the hydrophilic film 57, and only the gas and the liquid pass through the hydrophilic film 57, pass through the through-hole 55a, the passage 56, and the support member 53. And is discharged from the connection port 48.

The second filter 15B has substantially the same configuration as that of the first filter 15A. The second filter 15B has the same structure as that of the first filter 15A in that a water-repellent film is heat-sealed instead of the hydrophilic film 57 on the surface of each disk 55. Is different. In the second filter 15B, the sealing port 50
Is connected to the connection port 48 of the first filter 15A.
From 0, the dust and the cleaning liquid filtered through the particles are sucked and discharged from the connection port 49. While the cleaning liquid passes through the inside of the second filter 15B, only air bubbles mixed in the cleaning liquid pass through the water-repellent film on the surface of each disk 55, and
a, guided to the passage 54 of the support member 53 through the passage 56, the connection port
Emitted from 48.

The air pipe 16 has a flow control valve 13 and a pump.
The second filter 15 </ b> B is provided upstream of the filter 14. The second filter 15 </ b> B is provided with dust, particles, and the like in the compressed air supplied from the compressor (not shown) to each of the flow path control valves 13 and the pump 14.
Water and oil are removed.

By the way, air bubbles are generated in the cleaning liquid due to a chemical reaction during cleaning of the wafer of the hydrogen peroxide solution used as the cleaning liquid and pressure changes in the flow path control valve 13, the pump 14, the filter 15, and the cleaning liquid is subjected to the cleaning process. When the cleaning liquid is introduced into the tank 11, bubbles may be mixed into the cleaning liquid. In this embodiment, the water-repellent film is formed on each of the members constituting the liquid supply means, such as the pipe 12, the flow path control valve 13, the pump 14, and the filter 15. 21, 32, 46 and the like are provided, and air bubbles can be easily and reliably removed from the cleaning liquid when circulating and filtering dirt and particles in the cleaning liquid. Therefore, organic substances can be uniformly removed in wafer cleaning with the cleaning liquid, and the yield of semiconductor devices can be improved.

In this embodiment, the second filter 15B having the water-repellent film is used.
Is provided in the air pipe 16 and each flow path control valve 13 is
And removes dust, particles, water and oil in the compressed air supplied to the pump 14, so that the pump 14,
It is possible to improve the durability of the flow path control valve 13 and the electromagnetic valve 17 that supplies and shuts off compressed air to the valve 13 and the like.

[Effects of the Invention] As described in detail above, according to the present invention, air bubbles mixed into liquid are reliably removed by a flow path control valve, a pump, and a filter provided between a suction side and a discharge side in a liquid supply device. However, there is an excellent effect that the gas and the liquid can be surely separated.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram showing a cleaning liquid supply device according to one embodiment of the present invention, FIG. 2 is a partial cross-sectional view in the axial direction of the pipe, FIG. 3 is a cross-sectional view in the diameter direction of the pipe, and FIG. FIG. 5 is an enlarged sectional view showing a main part of the diaphragm, FIG. 6 is a sectional view showing a pump, FIG.
The figure is an enlarged sectional view showing a main part of the diaphragm, FIG. 8 is a sectional view showing a filter, and FIG. 9 is an enlarged sectional view showing a main part of a disk. In the drawing, 11 is a cleaning tank, 12 is a pipe, 13 is a flow path control valve, 14 is a pump, 15 is a filter, 19 is an inner pipe, and 20 is a through hole.

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Toru Matoba 2-1844-2 Kozoji-cho, Kasugai-shi, Aichi Prefecture Inside Fujitsu VSI Co., Ltd. (56) References JP-A 1-215312 (JP, A) 63-63609 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) B01D 19/00

Claims (3)

(57) [Claims] 1. A flow path in a liquid supply device having a liquid suction passage and a discharge passage, a valve body for shutting off between the suction passage and the discharge passage, and a diaphragm provided on an outer peripheral surface of the valve body. A control valve, wherein a number of through holes are formed in the diaphragm,
A flow control valve in a liquid supply device, wherein a water-repellent film is adhered to both surfaces thereof, and air bubbles in the liquid are exhausted to an exhaust passage through the diaphragm. 2. A liquid suction passage and a discharge passage, a liquid chamber provided between the suction passage and the discharge passage, and a diaphragm provided in the liquid chamber for reducing or expanding the liquid chamber. A pump in a liquid supply device having: a plurality of through-holes formed in the diaphragm;
A pump in a liquid supply device, wherein a water-repellent film is adhered to both surfaces thereof, and air bubbles in the liquid are exhausted to an exhaust passage through the diaphragm. 3. A first suction port for sucking a liquid, a first discharge port for discharging a liquid, and a first discharge port provided between the first suction port and the discharge port. A first filter portion having a support member having a main passage connected to the first member and a first disk connected to the support member; a first filter portion connected to the first discharge port to suck a liquid; A second discharge port from which liquid is discharged, a second discharge port from which liquid is discharged, a support member provided between the second suction port and the discharge port, and having a main passage connected to an exhaust passage; And a second filter portion having a second disk connected to the first disk. The first disk has a plurality of through-holes formed therein and a support passage connected to the main passage inside. And a hydrophilic film is applied to the surface of the second disk. A branch passage connected to the main passage is provided inside, and a water-repellent film is adhered to the surface of the branch passage. The liquid is filtered by the first filter portion, and the liquid is filtered by the second filter portion. A filter in a liquid supply device, wherein bubbles in a liquid are exhausted to an exhaust passage.